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In this issue:
Fermi Telescope Celebrates One Year of Science
Fermi Telescope Caps First Year With Glimpse of Space-Time
Reminder: All-Hands Safety and Security Briefings Today
SLAC Green Note: Check Out the Label

SLAC Today

Thursday - October 29, 2009

Fermi Telescope Celebrates One Year of Science

This view of the gamma-ray sky, constructed from one year of LAT observations, is the best view of the extreme universe to date. The map shows the rate at which the LAT detects gamma rays with energies above 300 million electron volts—about 120 million times the energy of visible light—from different sky directions. Brighter colors equal higher rates. (Image: NASA/DOE/Fermi LAT Collaboration.)

Just over a year after the Fermi Gamma-ray Space Telescope began taking science data, the collaboration is celebrating its many noteworthy results.

"With Fermi, we're seeing the gamma-ray sky at timescales we've never been able to probe before; we also see an energy range previously inaccessible to us," Fermi Project Scientist Julie McEnery said yesterday during a NASA media event publicizing the first year of Fermi telescope results. "With these missing pieces, we're finding many new things in the sky."  Read more...

Fermi Telescope Caps First Year With Glimpse of Space-Time

In this illustration, one photon (purple) carries a million times the energy of another (yellow). Some theorists predict travel delays for higher-energy photons, which interact more strongly with the proposed frothy nature of space-time. Yet Fermi data on two photons from a gamma-ray burst fail to show this effect, eliminating some approaches to a new theory of gravity. (Image: NASA/Sonoma State University/Aurore Simonnet.)

During its first year of operations, the Fermi Gamma Ray Space Telescope captured more than 1,000 discrete sources of gamma rays—the highest-energy form of light. Capping these achievements was a measurement that provided rare experimental evidence about the very structure of space and time, unified as space-time in Einstein's theories.

"Physicists would like to replace Einstein's vision of gravity—as expressed in his relativity theories—with something that handles all fundamental forces," said Peter Michelson, principal investigator of Fermi's Large Area Telescope. "There are many ideas, but few ways to test them."

On May 10, 2009, the Fermi telescope and other satellites detected a so-called short gamma-ray burst, designated GRB 090510. Astronomers think this type of explosion happens when neutron stars collide. Ground-based studies show the event took place in a galaxy 7.3 billion lightyears away. Of the many gamma-ray photons the LAT detected from the 2.1-second burst, two possessed energies differing by one million times. Yet after traveling some seven billion years, the pair arrived just nine-tenths of a second apart.

"This measurement eliminates any approach to a new theory of gravity that predicts a strong energy-dependent change in the speed of light," Michelson said. "To one part in 100 million billion, these two photons traveled at the same speed. Einstein still rules."

For more on the new result, see: Gamma-ray Burst Restricts Ways to Beat Einstein's Relativity, Symmetry Breaking, and the full NASA news release... (Note: NASA page may display incorrectly in Internet Explorer; it displays correctly in Firefox.)

Reminder: All-Hands Safety and Security Briefings Today

(Photo - SLAC flashlight)
These SLAC flashlights are among the giveaways for attendees of today's Safety and Security Briefing. (Photo by Paul Bloom.)

Everyone in the SLAC community is asked to attend one of four 70-minute sessions for the Annual Safety and Security Briefing in Panofsky Auditorium today. There will be free SLAC flashlights, calendars, pens and other giveaways for those who attend.

The program will include:

1. Event host, introduction and event overview - Brian Sherin
2. SLAC Director's Opening Remarks - Persis Drell
3. DOE/SSO Manager Opening Remarks - Paul Golan
4. Counterintelligence and Counterterrorism - Steve Minniear
5. The Wild, Wicked Web - Marilyn Cariola
6. Emergency Management - Lance Lougee
7. Influenza 2009 update - Manuel Hipol
8. Vehicle Safety - Gary Hormel, Director of Securitas Security Services

Four 70-minute sessions will take place in SLAC's Panofsky Auditorium. Please use the schedule below to determine which session you should attend to help avoid overfilling any one session.

8:30–9:45 a.m., last names starting A–F
10:30–11:45 a.m., last names starting G–L
1:30–2:45 p.m., last names starting M–R
3:30–4:45 p.m., last names starting S–Z

If you have questions, please contact Terry McMahon at (x3465) or Brian Sherin (x5082).

After the fair, please fill out the online evaluation. SLAC the ES&H Division will be awarding five $10.00 Starbucks gift certificates in a random drawing to five lucky winners who complete the form. Winners will be announced on November 5. 

(Image - ISEMS leaves)

SLAC Green Note:
Check Out the Label

According to TerraChoice Environmental Marketing's 2009 report, "The Seven Sins of Greenwashing," of 2,219 products surveyed in the United States and Canada making environmental claims, 98 percent committed at least one form of greenwashing. This term describes the act of misleading consumers regarding the environmental practices of a company or environmental benefits of a product or service.

TerraChoice recommends that consumers choose products with accredited logos from third-party agencies, rather than relying on general claims, such as "natural," "eco-friendly" or "biodegradable," that do not offer specific detail. Reliable eco-labels listed by TerraChoice include but are not limited to Green Seal, EcoLogo, Design for the Environment, Eco Cert, Energy Star, EPEAT, Forest Stewardship Council, Greenguard, Sustainable Forestry Initiative, USDA Organic, and WaterSense.

For help finding environmentally preferable products, see Environmentally Preferable Purchasing Resources or contact Alan Kong (x4138) of the Purchasing Department.


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